In order to detect a current which flows in a current path (for example, in a bus bar) which connects an in-vehicle battery of a vehicle and electronic equipments of the vehicle, a current detection apparatus is used. For example, as shown in Patent Literature 1, the current detection apparatus includes a core of a ring shape, a magnetic gap which is formed by opening a part of the core, and a Hall element which is arranged in the magnetic gap, and is configured so that the value of a current which flows in the current path which is inserted into the core of a ring shape is detected by the Hall element which is arranged in the magnetic gap.
Therefore, in the current detection apparatus, when a magnetic field is generated in the core of the ring shape by the current which flows in the current path, the Hall element in the magnetic gap generates a voltage (Hall voltage) due to Hall Effect in accordance with the magnetic field. At this time, the core functions to strengthen the magnetic field generated by the current which flows in the current path. Since the Hall voltage which the Hall element generates corresponds to the magnetic field strength in the core and corresponds to the value of the current which flows in the current path which generates the magnetic field, the current value can be detected.
In such current detection apparatus, in order to obtain a detection current in a sufficient level so that current detection performance may not be dropped, two Hall elements are provided in the magnetic gap of the core. Thereby, compared with the case of one Hall element, a current in almost two times levels can be detected. The two Hall elements are juxtaposed in the thickness direction of the core or the direction of magnetic force lines which pass the magnetic gap.
Thus, in the related-art current detection apparatus, a current in a desired level can be detected by providing two Hall elements in the magnetic gap of the core.